Anesthesia and analgesia
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Anesthesia and analgesia · Nov 1992
Comparative Study Clinical Trial Controlled Clinical TrialComparison among intrathecal fentanyl, meperidine, and sufentanil for labor analgesia.
This study compared the analgesic efficacy of intermittent injections of intrathecal fentanyl (10 micrograms), meperidine (10 mg), or sufentanil (5 micrograms) administered to 65 parturients during the first stage of labor. The groups did not differ in onset or duration of effective analgesia. The meperidine group, however, had significantly lower pain scores once cervical dilation progressed beyond 6 cm. ⋯ All neonates had a 5-min Apgar score of 7 or more. We conclude that intermittent intrathecal injections of fentanyl, meperidine, or sufentanil can provide adequate first-stage labor analgesia. Meperidine appears to provide more reliable analgesia as the first stage of labor progresses.
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Anesthesia and analgesia · Nov 1992
Effects of surgical stress and volatile anesthetics on left ventricular global and regional function in patients with coronary artery disease. Evaluation by computer-assisted two-dimensional quantitative transesophageal echocardiography.
We investigated the effects of halothane, enflurane, and isoflurane on central hemodynamics and left ventricular global and regional function when used to control intraoperative hypertension in 39 patients with coronary artery disease. Left ventricular short-axis, midpapillary images were obtained by transesophageal echocardiography. Using a centerline algorithm, we analyzed left ventricular images for global area ejection fraction (GAEF) and segmental area ejection fraction (SAEF). ⋯ Isoflurane induced a decrease in the SAEF/GAEF ratios of two segments corresponding to the inferolateral wall of the left ventricle that was, in one of these segments, significantly more pronounced compared with both halothane and enflurane. Halothane or enflurane did not cause any change in regional wall motion. We conclude that isoflurane is more likely to cause regional wall motion changes than halothane or enflurane in patients with coronary artery disease.
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Anesthesia and analgesia · Nov 1992
Comparative StudyA comparison of methods for the detection of myocardial ischemia during noncardiac surgery: automated ST-segment analysis systems, electrocardiography, and transesophageal echocardiography.
Clinicians often fail to detect intraoperative ischemic electrocardiographic (ECG) changes when viewing oscilloscopes. Automated ST-segment monitors promise to increase the detection of such ECG changes. We investigated the capacity of two commercially available ST-segment monitors to detect intraoperative myocardial ischemia in patients at high risk for developing intraoperative myocardial ischemia during vascular and other noncardiac procedures. ⋯ Comparison of the printed ECG with TEE revealed that ST-segment changes in the printed ECG, as analyzed by a cardiologist, were 25% sensitive and 62% specific for the detection of TEE-diagnosed myocardial ischemia. When T-wave inversions were added to ST-segment depression as a criterion for the diagnosis of myocardial ischemia by the printed ECG, the sensitivity of ECG for the detection of intraoperative myocardial ischemia, as determined by TEE, was 40% and specificity was 58%. Twenty-three of the 44 patients were simultaneously monitored in leads I, II, and V5 with an automated Marquette ST-segment monitor.(ABSTRACT TRUNCATED AT 250 WORDS)
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Anesthesia and analgesia · Nov 1992
Comparative StudyPreoxygenation of pregnant and nonpregnant women in the head-up versus supine position.
The influence of preoxygenation in the supine (n = 10) versus the 45 degrees head-up (n = 10) position on the duration of apnea leading to a decrease in arterial oxygen saturation to 95%, as monitored by pulse oximetry, was investigated in 20 women undergoing elective cesarean section at term of pregnancy. The results were compared with those obtained in a control group of 20 nonpregnant women. ⋯ We conclude that pregnant women desaturate their arterial blood of oxygen more rapidly than do nonpregnant women. Furthermore, the head-up position extends the duration of apnea that can take place before desaturation occurs in nonpregnant patients.
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Anesthesia and analgesia · Nov 1992
Comparative StudyComparison of two techniques to inflate the bronchial cuff of the Univent tube.
The Univent tube is an endotracheal tube with a movable bronchial blocker. The blocker cuff reportedly exhibits high-pressure characteristics when inflated to seal any adult bronchus. This study was aimed at measuring the cuff volume that would seal the bronchus when two different techniques of cuff inflation were used. ⋯ The bronchial cuff was then inflated until air bubbles ceased to appear in the beaker. Direct measurement of compliance of the blocker cuff confirmed its high-pressure characteristics. Bronchial sealing volume ranged from 3 to 5 mL when measured with the NPT and from 4 to 6 mL when measured with the PPT.(ABSTRACT TRUNCATED AT 250 WORDS)